osfmk/i386/fpu.h

   1 /*
   2  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56
  57 #ifndef _I386_FPU_H_
  58 #define _I386_FPU_H_
  59
  60 /*
  61  * Macro definitions for routines to manipulate the
  62  * floating-point processor.
  63  */
  64 #include <kern/thread.h>
  65 #include <kern/kern_types.h>
  66 #include <mach/i386/kern_return.h>
  67 #include <mach/i386/thread_status.h>
  68 #include <i386/proc_reg.h>
  69 #include <i386/thread.h>
  70
  71 extern int              fp_kind;
  72
  73 extern void             init_fpu(void);
  74 extern void             fpu_module_init(void);
  75 extern void             fpu_free(
  76                                 struct x86_fpsave_state * fps);
  77 extern kern_return_t    fpu_set_fxstate(
  78                                 thread_t        thr_act,
  79                                 thread_state_t  state);
  80 extern kern_return_t    fpu_get_fxstate(
  81                                 thread_t        thr_act,
  82                                 thread_state_t  state);
  83 extern void             fpu_dup_fxstate(
  84                                 thread_t        parent,
  85                                 thread_t        child);
  86 extern void             fpnoextflt(void);
  87 extern void             fpextovrflt(void);
  88 extern void             fpexterrflt(void);
  89 extern void             fpSSEexterrflt(void);
  90 extern void             fpflush(thread_t);
  91 extern void             fp_setvalid(boolean_t);
  92 #ifdef __i386__
  93 extern void             fxsave64(struct x86_fx_save *);
  94 extern void             fxrstor64(struct x86_fx_save *);
  95 #endif
  96
  97 /*
  98  * FPU instructions.
  99  */
 100 #define fninit() \
 101         __asm__ volatile("fninit")
 102
 103 #define fnstcw(control) \
 104         __asm__("fnstcw %0" : "=m" (*(unsigned short *)(control)))
 105
 106 #define fldcw(control) \
 107         __asm__ volatile("fldcw %0" : : "m" (*(unsigned short *) &(control)) )
 108
 109 static inline unsigned short
 110 fnstsw(void)
 111 {
 112         unsigned short status;
 113         __asm__ volatile("fnstsw %0" : "=ma" (status));
 114         return(status);
 115 }
 116
 117 #define fnclex() \
 118         __asm__ volatile("fnclex")
 119
 120 #define fnsave(state)  \
 121         __asm__ volatile("fnsave %0" : "=m" (*state))
 122
 123 #define frstor(state) \
 124         __asm__ volatile("frstor %0" : : "m" (state))
 125
 126 #define fwait() \
 127         __asm__("fwait");
 128
 129 #define fxrstor(addr)           __asm("fxrstor %0" : : "m" (*(addr)))
 130 #define fxsave(addr)            __asm __volatile("fxsave %0" : "=m" (*(addr)))
 131
 132 #define FXSAFE() (fp_kind == FP_FXSR)
 133
 134
 135 static inline void clear_fpu(void)
 136 {
 137         set_ts();
 138 }
 139
 140
 141 /*
 142  * Save thread`s FPU context.
 143  */
 144
 145 static inline void fpu_save_context(thread_t thread)
 146 {
 147         struct x86_fpsave_state *ifps;
 148
 149         assert(ml_get_interrupts_enabled() == FALSE);
 150         ifps = (thread)->machine.pcb->ifps;
 151         if (ifps != 0 && !ifps->fp_valid) {
 152                 /* Clear CR0.TS in preparation for the FP context save. In
 153                  * theory, this shouldn't be necessary since a live FPU should
 154                  * indicate that TS is clear. However, various routines
 155                  * (such as sendsig & sigreturn) manipulate TS directly.
 156                  */
 157                 clear_ts();
 158                 /* registers are in FPU - save to memory */
 159                 ifps->fp_valid = TRUE;
 160
 161 #if defined(__i386__)
 162                 if (!thread_is_64bit(thread) || is_saved_state32(thread->machine.pcb->iss)) {
 163                         /* save the compatibility/legacy mode XMM+x87 state */
 164                         fxsave(&ifps->fx_save_state);
 165                         ifps->fp_save_layout = FXSAVE32;
 166                 }
 167                 else {
 168                         /* Execute a brief jump to 64-bit mode to save the 64
 169                          * bit state
 170                          */
 171                         fxsave64(&ifps->fx_save_state);
 172                         ifps->fp_save_layout = FXSAVE64;
 173                 }
 174 #elif defined(__x86_64__)
 175                 /* for a 64-bit long mode kernel, we can always use plain fxsave */
 176                 fxsave(&ifps->fx_save_state);
 177                 ifps->fp_save_layout = thread_is_64bit(thread) ? FXSAVE64
 178                         : FXSAVE32;
 179
 180 #endif
 181         }
 182         set_ts();
 183 }
 184
 185 #endif  /* _I386_FPU_H_ */